Method of preparing maraschino type cherries



Oct. 29, 1935.

Filed April 2, 1934 Patented Oct. 29, 1935 PATIENT 1 OFFICE METHOD or rnEPAnnvG MAnAscmN y'rrrn onnaams William K. Tucker, Berkeley, Calif., assignor to California Packing Corporation, San Francisco,

Calif., a corporation of New York applicati@ April 2, 1934, serial No. 718,552 6 claims. (ci. 99-11) 'I'his invention relates to a method of preparing maraschino type cherries, and is more particularly related to a method of conditioning the cherries as to color and texture.

Historically, this type of cherry was supposed to have been rst made in the Dalmatian Mountains, where the native sour cherries (Marasca)I were preserved in brandy and cordial made from the same Marasca cherries. Cherries made elsel where in the same manner, or in a manner to simulate the original maraschino cherries, are

designated as maraschino type cherries, to which 'this application relates.

In preparing maraschino type cherries, the cherries are first treated inl a bleaching solution containing appoximately 1% sulphurous acid, or are subjected directly to the action of sulphurv dioxide fumes. Whatever the particulars -of the method used, it is essentially a bleaching process during which the reds of the cherries are bleached. When the cherries are not ripe and have no color, this process turns them into a canary or straw yellow color.

If there are any such marks as bruise marks from the wind, handling, sunburn, or'the like, this reducing agent will not bleach out the stains of these colors produced in the bruised portions of the fruit; These oir-color cherries will not dye'uniformly and are therefore "of very inferior quality. p

It lis therefore an object of my invention to 1 provide a method of preparing maraschino type cherries so that all cherries will be of a uniform color and texture and will dye uniformly to thereby increase the quality of the cherries prepared and the value of the cherries vto the packer.

Another object of my invention is to produce a method of preparing cherries of the maraschino type whichl includes the steps of subjecting the cherries to the action of a treating agent such, for example, as chlorine water, or a hypochlorite of suilicient strength to react to the coloring matter forming browns, yellows, or other discoloration of the cherries to produce cherries'of uniform color, but of strength insuiiicient to materially damage the pulp or texture of the fruit. v Y

Another object of my invention is to provide a method of preparing cherries of the maraschino like, remaining after the treatment of the reducagent so that substantially all -of the color is of the fruit does not follow the treatment with the secondary agent.

bleached from the cherries to produce cherries l0 Another object of my invention is to provide a method of preparing cherries of the maraschino type wherein following the customary/reduction of the natural red coloring matter of the cherries, cherries are submitted to the action of a second- 1l ary reagent providing chlorine in a form available for reaction .with the remaining coloring matter of the cherries so that such coloring as has been produced in the pulp of *the cherries by sun, wind, or other bruises, isbleached from the 20 cherries.

Other objects of this invention it is believed will be apparent from the following detailed description of the preferred embodiment thereof.

In the drawing I have di'agrammatically illus-f25 .trated the process embodying my invention.

I have discovered that in the preparation of maraschino type cherries, cherries substantially free from spots and of substantially uniform color` may be prepared and that all color spots 30 or portions of the cherries may be bleached from the cherries to produce cherries the texture or pulp' of which is not materially altered by the treating of the cherries after they. have been first subjected to the ordinary reducing action or process as commonly heretofore employed with a secondary bleaching agent which will unite with the coloring matter remaining after the reduction o f the coloring matter of the cherries, and

' matter from the cherries may b e -eiectively bleached therefromv by secondary bleaching agents which are most effective in neutral or acid solutions and that secondary bleaching .agents which Aare dependent for their bleaching action 50 upon being utilized in solutions of analkaline character can not be successfully employed without encountering the danger of the pulp of the cherries sloughing away under lthe influence of M the secondary bleaching agent in an alkaline solution.

In accordance with the preferred process embodying my invention, the cherries are first subjected at I to the action of sulphur dioxide either in solution as sulphurous acid or under the influence of fumes of sulphur, or a solution of sulphurous acid/salts to bleach the natural organic coloring matter of the cherrieswto the corresponding leuco` base.

In accordance with this process as commonly followed, cherries, preferably white and unripe, are bleached in a solution containing approximately 1% sulphurous acid calculated as sulphur dioxide. The strength of this solution lmay vary from 0.5% to 2.0%'. The solution may also be varied by some metal, such as calcium (lime) or soda, being added. In such case the preserving solution may be in part or in whole calcium bisulphite or sodium bisulphite. Under usual manufacturing conditions, a small amount of calcium hydroxide is added to the sulphurous acid solution and no doubt 'the "preserving solution is a mixture of calcium sulphite andlime or so-called calcium bisulphite, etc.- Again in sor're processes the cherries are allowed to come in contact with the fumes of burning sulphur for a proper period of time and' then placed in a solution of salt (NaCl) Whatever the detailsof the primary bleaching Amethod utilizing the reducing agents as above set forth, the process has for its object the removal of the natural color from the cherries and the preservation of -the fruit yuntil it is ready for processing. f Cherries in brine as thus produced is an article of manufacture and is often sold in thisfcondition. When carrying out the process above defined of subjecting the cherries to the action of reducing agents, cherries which are not Iripe. and have no color are turned by this process-or bleach into a canary or straw yellow color. The marks on the cherries such as bruise marks from the wind, handling, sunburn, or the like, are not removed by the reducing process. If the cherries have started to ripen so that they have red cheeks, asin the case of Royal Anne cherries, they will -not be entirely bleached but will sometimes show dark yellowish brown spots` vwhere the reddish color had been before bleaching, and alight straw yellow background.

The cherries containing the spots as above set spots through the artificial coloring matter. Such cherries are known to the trade as whole and spotted" and command a price from one-quarter to `one-third that Yof perfect cherries.

In accordance with the process embodying my v invention, the cherries, after the primary reduction, are washed free at 2 of sulphur dioxide, then pitted at 3, and sorted at 4. The spotted cherries are then subjected at I* to the action of the secondary bleaching agent, the strength and charlacter of which are sutlicient to remove the stains chlorite and the like. The secondary bleaching agents which may be utilized for carrying out the secondary bleaching away of the spots of the whole and spotted cherries are principally such oxidizing agents as are effective in neutral or acid l solutions such as chlorine and water, sodium or calcium hypochlorite, or other reagents including chlorine in its available form, and the like. Oxidizing agents which depend for their oxidizing action upon the presence of an alkaline or neutral lo solution such, for example, as hydrogen peroxide, sodium perborate, and the like, are not effective for the removal of spots from the whole or spotted cherries without causing sloughing oi' the cherry pulp or disintegration of the cherries, 15 and it is not believed that these agents could be used`commercially for the removal of the spots from whole or spotted cherries.

After the cherries have been subjected to the secondary bleaching action at I, they are washed l) again as indicated at 2e, or they may be placed in a brine of salt (NaCl) and sold in that condition. When they are utilized for the purpose of producing the maraschino type cherries, they are washed asat 2a and after being washed, are placed in 9 5 suspension in a dilute sugar solution containing ,the proper amount of coloring matter.

The cherries are sorted at 4 and the unspotted cherries are colored or dyed at 5 and are packaged at 6 or are sold without coloring as maraso schino type cherries ready for dyeing, as desired.

The spotted cherries separated vat l from the unspotted cherriesxare then subjected to a secondary bleach I, and as an illustrative example, the manner in which my invention is carried out 35 utilizing, for example, sodium hypochlorite, I proceed preferably as follows:

iWhole and spotted cherries, after they have been washed free of the primary reducing agent such as SO2, are placed in a solution of sodium 40 hypochlorite, utilizing preferably about one-half v.

per cent, or itsyequivalent, in free chlorine. The cherries are allowed to remain in this solution until the ybleach becomes complete. Small amounts ofychlorine, or chlorine compounds., may i5.. v

be 'added to the bleach if necessary to fortify the solution so thatthe concentration iskept constant despite the addition of water from the washed fruit or -the loss of chlorine by volatilimtion. I prefer, when carrying out this secondary bleach- 5g)4 ing, to use an acid such as acetic acid, to slightly acidity the solution, as the use of an acid causes the secondary bleach to proceed more rapidly and more effectively, and to produce cherries which are of a more uniform and, lighter color than 65 where the solution is not made acid. After a sufficient length of time, the whole and spot cherries bleach from a straw yellow to a. more or less transparent white, according to the chlorine compound selected. For example, sodium hypom I chlorite, in the presence of an acid, gives the cherries a more transparent appearance than cherries prepared with calcium hypochlorite or with chlorine gas (dissolved in water).

'yThe cherries produced when using chlorine 'water in the presence of an acid are whiter and more opaque.` The effect of other oxidizing agents. effective in an acid solution or a neutral solution vary slightly from thatpf hypochlorite or free chlorine, but each operates to remove or bleach from the cherries the color remaining after the cherries have been subjected to the primary color reduction, utilizing sulphurous acid, sulphur dioxide, or other reducing agents.

In accordance with myinvention. after the n cherries have been suiliciently bleached, the vchlorine or hypochlorite is removed from the cherries by washing with water at 2".

- There are many variations that can be made in the method of removing the coloring matter by the use of the above set forth oxidizing agents. The strength of the oxidizing agent may be'varied and can be changed to meet the particulargrade and type of cherries treated. It is usually found, however, that calciumor sodium hypochl'orite,l

l equivalent to 1% chlorine (compared to the weight of the cherries) is suilicient to carry out l'the process of oxidizing the remaining coloring calcium' or sodium hypochiorites on each ofthree successive days to "give a total of three applications'vof hypochlori'tes or equivalent oxidation in the` cherries in the amount of 1% chlorine. f

After the treatment with the secondary bleach'- ingy agent, it is sometimes advisable to again treat the cherries with sulphurous acid in the manner of the original treatment with the rev ducing agent, and in my preferred process, afterA the seeondary bleaching agent has been thor-` o'iighly v washed from the cherries, the cherries are again treatedin a sulphurous acid solution and allowed 'to stand in this sulphurous acid solution for a few days. Fjollowing the subsequent treatment of lthe sulphurous acid, the cherries are' washed free from the sulphur dioxyde to ug'liereitherel is no more than a trace o fy sulphur dioxide left in the cherries. The cherries are then colored or dyed at 5* or sold as-niaraschino type cherries ready for dyeing, as desired.

-f In brief, .my invention consists in the preparation of maraschino type cherries where the chero ries are vsubjected to the action of a reducing agent and a secondary bleaching agent which acts to remove the spots and color left after treatment with the reducing agent, in washing the cherries free of the reducing agent before they are subjected to the secondary bleaching action, and in the use of a secondarybieaching agent which will bleach away the color remaining after the primary bleach without causing sloughing or deterioration of the pulp of the cherries,A and in the carrying out of thissecondary bleaching,

either., in a neutral or acid solution, where it is found most eifective.

Having f ully describedniy invention, it is ,to be understood that I do not wish to be limited to the details herein set forth, but my invention is 5 of the full scope of the appended claims.

I claim:

1. A method of preparing maraschino type cherries which includes `the steps of subjecting the cherries to the action of sulphur dioxide to lo reduce the natural organic coloring rnat'ter of the cherries, washing the cherries free of ,the sulphur dloiide, and th'en treating the cherries with asolution of hypochlorite to bleach the remaining colors of the cherries. 1;,

, 2.` A method of preparing cherries which includes the steps offsubj'e'ctin'g cherries to the action of the sulphur vdioxide to reducel the nat-3 ural organic coloring matter of the cherries,

washing: the cherries freof the sulphur dicxlde',,` go and then treating the cherries with an acid solution of hyppchlorite to bleachthe remaining colors of the cherries.

3. A method of preparing maraschino type cherries which includes' the steps of subjecting 2;,`

the .cherries to the action pf Sulphur diende to reduce the `natural organic colprina matter of the cherrieafreeing the' cherries of the dioxide, and then treating the cherries with a` mildj solution of sodium hypochlorite. ou 4.`A method 'of preparing maraschinotype cherries which includes the steps of subjecting -the cherries to the action of 'sulphur dioxide to reduce the natural organic coloring matter of the, cherries, freeing the cherries off sulphur dioxideds and then treating the cherries with'a mild lsolution. of calcium hypochlorlte.

5. A method Aof 'preparing maraschino type. cherries which includes the steps of subjecting the cherries'to the action'oi sulphur dioxide to 40 reduce the natural organic coloring matter of the cherries',\washing the cherriesv free of the sulphur dioxidefand then treating the cherries in an acid solution of sodium hypoohlorite to bleach the remaining colors of the cherries. 45

6. A lz r'reihod of 1 preparing maraschino type cherries which includes the stepsv of subjectingv the cherries to the action of sulphur dioxide to reduce thenatural organic coloring matter of the cherries, washing the cherries freeof the sulphur 50. dioxide, and then treating the cherries in an acid solution of 'calcium hypochlorite to bleach the remaining colors of the cherries.

' K. TUCKER. 

